FastCGI protocol

Scenario

• Imagine we have an http server which has two instances. One is responsible for processing fcgi protocol requests, and the other is responsible for http requests.
• Host：example.org
• Requests that start with / fcgi are forwarded to the fcgi protocol service instance with address 10.0.0.1:8001
• Other requests are forwarded to http service instance with address 10.0.0.1:8002

Configuration

Modify example configurations (conf/) as the following steps:

• Step 1. Config path of forward rules in conf/bfe.conf

hostRuleConf = server_data_conf/host_rule.data
routeRuleConf = server_data_conf/route_rule.data
clusterConf = server_data_conf/cluster_conf.data

clusterTableConf = cluster_conf/cluster_table.data
gslbConf = cluster_conf/gslb.data  

• Step 2. Config host rules (conf/server_data_conf/host_rule.data)

{
    "Version": "init version",
    "DefaultProduct": null,
    "Hosts": {
        "exampleTag":[
            "example.org" // host name: example.org=>host tag: exampleTag
        ]
    },
    "HostTags": {
        "example_product":[
            "exampleTag" // host tag: exampleTag=>product name: example_product
        ]
    }
}

• Step 3. Config cluster configuration (conf/server_data_conf/cluster_conf.data) Note: Set backend conf params and use default value for other params

{
    "Version": "init version",
    "Config": {
        "cluster_demo_http": {                   
            "BackendConf": {
                "TimeoutConnSrv": 2000,
                "TimeoutResponseHeader": 50000,
                "MaxIdleConnsPerHost": 0,
                "RetryLevel": 0
            }
        },
        "cluster_demo_fcgi": {                    
            "BackendConf": {
                "Protocol": "fcgi",
                "TimeoutConnSrv": 2000,
                "TimeoutResponseHeader": 50000,
                "MaxIdleConnsPerHost": 0,
                "RetryLevel": 0,
                "FCGIConf": {
                    "Root": "/home/work",
                    "EnvVars": {
                        "VarKey": "VarVal"
                    }    
                }
            }
        }
    }
}

• Step 4. Config instances of cluster (conf/cluster_conf/cluster_table.data)

{
    "Version": "init version",
    "Config": {
        "cluster_demo_fcgi": {         // cluster => sub_cluster => instance list
            "demo_fcgi.all": [{        // subcluster: demo_fcgi.all
                "Addr": "10.0.0.1",
                "Name": "fcgi.A",
                "Port": 8001,
                "Weight": 1
            }]
        },
        "cluster_demo_http": {
            "demo_http.all": [{
                "Addr": "10.0.0.1",
                "Name": "http.A",
                "Port": 8002,
                "Weight": 1
            }]
        }
    }
}

• Step 5. Config gslb configuration (conf/cluster_conf/gslb.data)

{
    "Hostname": "",
    "Ts": "0",
    "Clusters": {
        "cluster_demo_fcgi": {   // cluster => weight of subcluster
            "GSLB_BLACKHOLE": 0,   // GSLB_BLACKHOLE == 0 means do not discard traffic
            "demo_fcgi.all": 100 // weight 100 means all traffic routes to demo_fcgi.all
        },
        "cluster_demo_http": {
            "GSLB_BLACKHOLE": 0,
            "demo_http.all": 100
        }
    }
}

• Step 6. Config route rules (conf/server_data_conf/route_rule.data)

{
    "Version": "init version",
    "ProductRule": {
        "example_product": [    // product => route rules
            {
                "Cond": "req_path_prefix_in(\"/fcgi\", false)",  
                "ClusterName": "cluster_demo_fcgi"
            },
            {
                "Cond": "default_t()",
                "ClusterName": "cluster_demo_http"
            }
        ]
    }
}

• Step 7. Verify configured rules

curl -H "host: example.org" "http://127.1:8080/fcgi/test"  
# request will route to 10.0.0.1:8001

curl -H "host: example.org" "http://127.1:8080/http/test"  
# request will route to 10.0.0.1:8002